sorting out an old floor

[dGray]

Hi All,

I'm hoping for some advice here. We have a 1910 house, and have just had a builder take down an internal wall and replace it with steels. We now have a big room, but the floor needs attention.

Half the floor is now a concrete slab, and the other half is a mix of brick, and no brick (raw soil) The original brick section had chipboard on which was damp and rotting.

So I'd like to know what are the options are to sort it all out, and preferably get one slab. I'd like the finished floor to be timber boards.

My ideas?
Do the bricks need to be removed, and dug down to be replaced with Gravel, DPM, sand, insulation, Concrete? sounds expensive, and hard to match to the existing slab.

Or can I fill in the soil areas with gravel/concrete, and coat the brick area with moisture-curing polyurethane. Self leveling compound on top.

Keen for any advice, as this must be a common thing on old houses.

Thanks
David

 

[regsmyth]

Chances are there's no dpm under the concrete bit. Is there a damp proof course in the outer walls?
Best thing, I think, would be to dig it all out and fit a ventilated, insulated timber floor. Big job though.

 

[dGray]

Outer walls have a bitumen damp proof course. Nothing that I can see under the slab.

That is a much bigger job to remove the whole floor, and replace with a different style.

 

[theprinceofdarkness]

Chances are, that there in no insulation under the concrete bit.
Frank

 

[regsmyth]

Well of course you could just fill in the gaps, level it all, lay some polythene, and put a floating timber floor over that, but it's only a matter of time before it fails. You'll be trying to hold back a lot of moisture. You'd probably get condensation on the boards. Bad idea.

 

[ivixor]

Perhaps concrete to level then ceramic/stone tiles over the lot. You don't need to worry so much about damp then.

 

[dGray]

thanks for the replies.

After taking out the bricks today i think I've go my head around this job.

Perfect solution would be to take up everything, including the old slab and replace all in one go with an insulated slab.

As the existing slab has been there a while, and there doesn't seem to be a damp problem in that area i intend to keep it, but paint on a damp proof liquid.

The other section will be a new insulated slab with a normal DPM. I've removed the bricks today and dug down to the bitumen layer and this seems ok.

 

[regsmyth]

You shouldn't put a timber floor on it though.
You might think the existing slab "doesn't seem to have a damp problem", but if you tape some polythene over it, chances are quite a lot of moisture will collect on the underside.

Bear in mind that where it's uninsulated it will also be cold, so the surface will collect condensation. If that condensation is on or at the bottom of your timber floor, you'll have some problems.

Also at the edges, where the slab meets the walls, you might get the same sort of problems.